1. Field of the Invention
The present disclosure relates to an integrally-formed camera module and a manufacturing method thereof.
2. Description of Related Art
As illustrated in FIG. 1, a camera module generally includes a lens barrel 12 including a lens, a holder 13, an IR (Infra-red) filter 14, an image sensor 15 and a PCB (Printed Circuit Board). The camera module receives an optical image of an object via a lens, transmits the optical image to IR filter 14, where the IR filter 14 interrupts the infra-red from the received optical image and sends the infra-red removed image to the image sensor 15, and where the image sensor 15 converts the irradiated optical image to an electrical signal.
At this time, the lens assembled on the lens barrel 12 is configured to perform a focusing work to obtain a most clear image by focusing through distance adjustment with the image sensor 15. That is, threaded units are formed at a coupling area between the lens barrel 12 and the holder 13 so that the lens barrel 12 and the holder 13 are coupled by threaded coupling, thereby enabling a simplified focusing work and performing a fine adjustment and then some.
However, the conventional screw-coupled camera module may create the following disadvantages if tension force between a threaded part of the lens barrel 12 and that of the holder 13 is inappropriate, because the focusing work is performed by rotating and coupling, by an operator, the lens barrel 12 using a device.
First, in a case the tension force is low, an appropriate tension force between the lens barrel 12 and the holder 13 cannot be maintained to generate an image defocus due to random rotation of the lens barrel 12 during the coupling process (hook-up) between the lens barrel 12 and the holder 13, whereby the hook-up becomes loose to loosen the threaded coupling and to decrease the resolution.
Conversely, in a case the tension force is high, image defects are generated by foreign objects generated by friction between threaded parts, although focusing may be performed by rotating the lens barrel 12 due to high tension force in a case the tension force is high.
Another disadvantage is that supply efficiency of good quality parts drastically decreases due to an inevitable presence of deviation between cavities, in a case a formability-deprived design is applied due to tendency of lightweight and slim camera module and introduction of multi-cavity for enhancing a productivity, because the lens barrel 12 and the holder 13 are currently injection-molded using plastic injection mold.
Lastly, in a case the lens barrel 12 and the holder 12 are fixed using an adhesive, the adhesive is leaked out to the outside to form a protrusion (A), rendering an exterior look to be unbecoming.